Inside
by MochiUs
Summary: They fucked. They loved. Rinse and repeat.
1. Chapter 1

With each sound, with each broken moan that escaped Tanjirou's lips, the molten heat in Giyuu's core would be set ablaze, burning him with a need that cannot be tempered through butterfly kisses and thorough necking. Nothing, not even his resolution to be as still as stagnant water, could stop the torrent of emotions that flooded his nerves every time Tanjirou arched his back and let out a choked cry of his name.

This was one of the few moments Giyuu truly felt alive, where passion ignited his veins and love consumed his soul. His broad hands unbuttoned Tanjirou's uniform and parted the front. He watched as lust pooled in his eyes. Red creeped up his lover's scarred chest

"Giyuu," Tanjirou would let out a tremulous gasp as Giyuu traced the scars on his chest with a reverence gods wished they could receive from their worshippers.

"Beautiful," Giyuu said with a rumble in his chest, massaging Tanjirou's pecs while thumbing his pebbled nipples.

"Does this feel good, Tanjirou?" He asked as he tweaked one nub between two fingers.

The man beneath him jerked from his touch. His breath came out in heavy pants. "Yes, it does." His eyes were hazy and glazed.

"You don't know how much I lose control when I'm with you," he said and plucked a pretty nipple meanly.

"Hah!" Tanjirou moaned out loud, but covered his mouth in embarrassment.

To be silenced was a crime.

Giyuu dove down and his mouth latched onto the other, suckling his teat and teasing it with his tongue.

Tanjirou cried out like an angel, singing out Giyuu's name like a prayer. His hands grasped his raven strands for purchase. He involuntarily pulled him closer, and in return, Giyuu played with his nipples until Tanjirou begged him to stop. Giyuu hummed as his hands explored his body, stopping to grope his ass with a firm grip.

"Please!" Tanjirou whined with a needy voice.

Giyuu was weak to such a lovely plea. When he let go with a resounding pop, Tanjirou's nipples were erect and swollen with a couple of teeth indents circling them.

Kind, warm hands tugged on his uniform, distracting Giyuu from admiring his work. "Off," Tanjirou demanded with pouty lips. "You're wearing too much."

"I see," Giyuu said.

There was a pause, one long enough for Tanjirou to be concerned. "You don't have to if you want," he said hurriedly. "We can hump each other instead," he flushed, searching for signs of discomfort.

They were still new in the dating scene, fumbling around each other as idiots in love. It took years to establish a stable lifestyle after Muzan was destroyed, and the trauma they experienced delayed many milestones. So many excuses, so much pain gave them reason to hold back their desires.

Then Giyuu slipped off his uniform with deft hands and precise speed. No movement was wasted as more and more skin was exposed.

"Tanjirou," he said with full intention.

Tanjirou felt his skin tingle under his intense gaze as the man stripped off his layers. Heat pooled in his belly when Giyuu took his hand and placed it on his groin. Tanjirou turned red as his palm covered his bulge. He also gulped as he measured his size and understood how much Giyuu wanted to fuck him.

"I want you," Giyuu helped him remove his belt and pants. "I want you very much."

"Me too," Tanjirou admitted and pulled down Giyuu's pants until his shaft was freed, which made Giyuu hiss at the first bite of cold.

With a slight apology in his eyes, Tanjirou widened his legs and spread them apart. His cock strained against his fundoshi, leaving wet patches at the front.

"I'm so wet for you," he breathed out and bit his lower lip, barely containing his desire. "I want you so bad."

Giyuu salivated at the image, cock hardening at the sight. He quickly grabbed the container of oil he laid on the side and poured them on his fingers until they were slick. Tanjirou vibrated as the man rubbed his fingers together, warming them before he could open Tanjirou open.

Giyuu pulled his fundashi aside and rubbed one digit against his entrance. "You're so tight for me," he crowed and entered with practice.

Tanjirou breathed in and felt his walls clench around the intrusion. He clawed his discarded haori as Giyuu plunged carefully at a steady pace, but nothing could steady his rapid heartbeat. His ears rung with each obscene squelch because all he could hear is his hole being impaled. His nose was overwhelmed with musk and heady sweat.

"Relax," Giyuu recaptured his lips and pumped Tanjirou's cock with his free hand. He swallowed the redhead's moans and added another finger with more difficulty. He pumped his fingers in and out while searching for the spot that would leave Tanjirou an unsatiated animal.

Tanjirou was lost and writhed beneath his ministrations, feeling those fingers scissor him apart. He rocked back to chase against the sensation like a paid whore and clenched again for more.

Giyuu dirtily deepthroated him with his tongue and plunged to the back of his throat, tangling his tongue with his like a vice. He stole his air and his heart, and when he finally reached his pleasure button, Tanjirou bucked his hips with a scream.

"Ah!" He arched his back as euphoria shot up his spine. "Yes! Right there!" He cried out as Giyuu thrusted his prostate with precision.

He surrendered and braced his hands on Giyuu's shoulders, moving along with his unmerciful thrusts. Two fingers turned into three, and Tanjirou took them like a slut until he was sopping wet. His cock wept to be touched. He never felt so loose and sloppy and desperate for release. Before he could reach orgasm, Giyuu cruelly wrapped his hand at the base of his cock and squeezed. Then he removed his fingers, leaving Tanjirou's poor puckered hole empty and alone.

"No, no, no." Tanjirou felt tears slide down his cheeks. "Please," he rubbed against his thigh. "Fill me up. Pump me with your seed," Tanjirou begged. He was no longer ashamed when his climax was wrongfully stolen from him.

"Then present yourself," Giyuu said as he sheathed his cock with oil, preparing himself for Tanjirou's sweet ass. "Show me," he growled. "Show me how much you deserve this."

He groaned as Tanjirou slipped the fundashi off his legs and threw them to a corner, leaving no room for imagination. Naked and exposed, he pulled his knees to his shoulders, almost folding himself in half. The man with sunlight in his smile looked away, almost shyly, as his fingers slowly spread his slick entrance apart, inviting for him to enter easily. It continued to clench around nothing, as if it anticipated to be wrecked and ruined.

"Only you," Tanjirou said in a small voice. "This is only for you."

Giyuu felt himself throb. He looked delectable. He looked perfect.

He looked ready to be full of his cock.

Therefore, Giyuu held his hips with a bruising grip and slammed into him until he bottomed out. Tanjirou let out a choked, voiceless scream and saw stars.

Giyuu relentlessly pounded into that tight heat with quick, powerful thrusts. Deep in pure bliss, Tanjirou dug his nails deep into Giyuu's back, scorching him with scratches and blood. His hole was stretched to the limits, and without fail, he let out an erotic sound every time Giyuu pistoned back in, pushing Tanjirou against the futon back and forth like a toy.

"H-harder," Tanjirou stuttered after one deep thrust and keened.

Drool seeped out of his mouth. His hand traveled to the underside of his abdomen and felt the faint outline of Giyuu's cock driven into him.

It was as if Giyuu claimed him and molded his insides to the shape of his cock. Without breaking rhythm, Giyuu pinched his nipples and fondled his chest, squeezing his breasts roughly until they were overstimulated and sensitive.

He drove Tanjirou mad.

"No-hah! Not there!" He sobbed.

"You don't like this?" Giyuu asked innocently and kissed one perky nipple. Tanjirou almost arched into his touch and groaned when Giyuu stopped midway.

"But I'm close," Tanjirou whined and raised his hips in hopes of finishing off but was left defeated when the Water Pillar made no move.

"I asked you a question."

Tanjirou muffled his scream of frustration with the pillow.

Giyuu went at a snail's pace, prodding him shallowly until he got the answer he wanted. "You don't," thrust, "Want," thrust, "This?"

Tanjirou doesn't know if Giyuu truly wanted to know, or if he was insecure over where his heart lied. However, just like how he would fight through hell and back for his sister, he would drag Giyuu into the heavens to prove him his worth. He sat up and wrapped his arms around Giyuu in an embrace.

"Tanjirou?"

Said man sank down into his length with a shudder, letting Giyuu know how much he unraveled him through the whispers into his ear.

"I do," Tanjirou gradually bounced back into his cock. "I love you so much, I don't know what to do."

"Tell me," He panted as his earrings swayed with his motions, "Can you tell me what to do?"

Giyuu was more of a man of action than words. Tanjirou yelped when he groped his cheeks and gripped them tight.

"Fuck," Giyuu cursed, "Fuck."

Like a snapped band, he rammed right into his prostrate. Tanjirou screamed.

With just his strength, Giyuu held Tanjirou still and plunged back into his hole again and again without reprieve. He fucked him hard and good to the point the man almost blacked out from the sheer force of his thrusts.

Tanjirou sunk into a space that left him reeling from the pleasure because that was all he felt. If his existence was only this, being fucked day and night from the man he adored and love, then he wouldn't mind this life. Only cries of Giyuu's name spilled from his lips, and somewhere along the way, he reached his peak. It was as if the orgasm was punched out of him.

"Giyuu!" He gasped as he stiffened and felt his insides flutter. Spurts of come spilled out and painted their abdomens. The climax was so intense that a bit reached his chin.

The aftershocks of his orgasm immobilized him, but he still felt Giyuu climaxed afterwards, muffling out his name on his shoulder and filling his walls with hot seed. They slowly rocked back to each other, milking their come until there was nothing left. They slipped into a languid, boneless kiss, and Giyuu went the extra mile to leave more hickies, suckling patches of skin until Tanjirou was covered head to toe with dark bruises. He had his own marks to bear, too, based on the soreness on his back.

Tanjirou always felt sad this part as Giyuu pulled out. The semen was already beginning to escape, and Tanjirou was too exhausted to clean up.

In gentle arms, Giyuu carried him and almost stumbled by the sudden weakness in his legs. Tanjirou softly laughed and nuzzled against his chest, cheek listening for his beating heart.

The scent of sex and contentment washed over him.

"I love you," Tanjirou smiled and hummed, knowing that his lover would wash him with a heated bath and care for his aches and pains.

The wind blew, and the chimes near their door clinked against each other, distracting him from the rarest of occasions. Tanjirou swore he heard the hint of a confession from Giyuu's end, but he was unsure.

No matter. The second round would do the talking for him.


	2. Chapter 2

Tanjirou hissed as he pushed himself up, already throbbing from his lower back as he prepared to get up for training. He lost balance and slipped back into the bed with a disgruntled moan. The aches from the night before caught up to him, and Tanjirou hissed as he felt a zing up his spine. Before he made his second attempt, struggling to lift himself up like a newborn fawn, a pair of muscled arms wrapped around his torso and kept him hostage.

"Giyuu-san," Tanjirou huffed as the man nuzzled against the nape of his neck, spooning him from behind. "Please let me go."

He then felt the phantom touch of a finger circling his rim, teasing his insides for something bigger, and gasped as he accidentally bucked back, feeling a well-endowed bulge against the crack of his ass.

"You're sore," Giyuu stated.

"And whose fault is that," Tanjirou groaned as Giyuu rubbed against him persistently.

A ball of pride swelled within the older man, knowing it would be _his_ fault that Tanjirou would be limping all day, letting out small sounds as he would adjust his seating position. His friends would give him strange looks as he shifted to and fro, unbeknownst of his previous nightly activities. Giyuu moved off the bed to grab some ointment, lubricating his fingers until they were slick and wet. He pressed a kiss at the dip below his lover's back, massaging his tense cheeks until Tanjirou was pliant beneath him.

"You're still a bit swollen," Giyuu said as he applied the ointment to Tanjirou's puckered rim with care.

Tanjirou closed his eyes with a blush reaching his ears and rocked against those nimble fingers, whining for him to enter inside. In the past, he always tried to reassure Giyuu that their rough lovemaking felt good, that he was a sturdy man and wouldn't feel pain. Giyuu often chastised him for that self-sacrificing nature, but he was partly at fault for loving too fiercely, too passionately.

"No, Tanjirou," Giyuu said sternly. "Look," he put more pressure, causing Tanjirou to gasp by the sudden stab of pain, "Let's do it more gently this time."

There were rare moments when Tanjirou allowed childishness to take the reins, but this called for desperate measures.

"Please Giyuu-san," Tanjirou whined and took his hand, dragging it directly to the seam of his entrance without warning.

He moaned aloud and shuddered as a finger breached him.

"Look," he rocked against that finger for more friction, more heat. "Do you feel that?"

He entered one of his own fingers alongside Giyuu's, for he was already addicted to how they caressed his inner walls. He clenched around them to pull them further inside to prove a point. "I'm still loose for you," he said with a sultry voice as he fucked himself slow and steady.

His mouth watered at the thought of being molded by Giyuu's cock, ramming into him like a tsunami.

"Please," he whined and rubbed against the sheets, crying out for Giyuu's name to fuck him hard and good. "I need you, I need you, I need you."

However, his prayers were ignored as Giyuu pinned his wrists above his head, and Tanjirou was again reminded of the Water Pillar's strength, of how this very man rose the ranks among the demon slayer corps. He leaned forward and bore his eyes into his sinful soul.

"No," he growled, leaving poor Tanjirou hot and bothered and empty. He clenched around nothing and whimpered from the demonstration of strength.

"I've been patient," he said coldly, "But it seems that my feelings do not matter."

"No!" Tanjirou protested and writhed. "They do," he tried to free his wrists.

"You've been bad," Giyuu said with disapproval and easily flipped his brat on his stomach. Tanjirou's cock ached to be touched, to be fondled, but Giyuu must have spoiled him too much. "Please," the boy hiccuped as fresh tears began to slide down his cheeks. "I'm sorry," he said and spread his cheeks to show him his rosy entrance, just how Giyuu liked him. The attack was effective, but Giyuu's restraint was stronger than any chain.

Yes, he was inclined to split Tanjirou on his cock until he was a drooling, simpering mess, but he was bad. Bad boys do not deserve rewards until they seriously contemplated their behavior.

Therefore, Giyuu took for himself and lapped at his hole, eating him out and enjoying how Tanjirou thrashed and writhed beneath him, helpless as his tongue dove deeper to places unknown. He restricted his arms behind his back and smiled as the boy pitifully rubbed his aching cock against the sheets.

"Feels good?" Giyuu asked.

"Yes, yes, yes," Tanjirou babbled, lost in his haze of lust and thrusted backwards to get his tongue deeper. "It feels – hah – it feels – hah – need you."

Tanjirou felt a tingle went up his spine and tried to muffle his cries, but his efforts were thwarted as Giyuu licked from his balls to his taint. He smacked his perky ass to stop him from moving, but that must have been the wrong move. Tanjirou suddenly cried out as he spurted out droplets of cum, spasming around Giyuu's tongue until he collapsed into the stained sheets.

"Oh no," Tanjirou wept softly once he regained himself and flinched as Giyuu pushed aside his bangs. He looked absolutely guilty not doing anything in return, a face Giyuu had to fix immediately.

"It's fine, Tanjirou," he rubbed circles at the small of his back and drank in his teary-eyed expression with delight.

"But," Tanjirou tried to roll over to face him but was hindered once he felt Giyuu slot himself against his backside. Another smack to his butt, and it forced out an involuntary moan. The sound echoed in the room, and Tanjirou, mortified, covered his mouth.

"Hearing you make these pretty sounds are enough for me," Giyuu whispered in his ear and latched on it, sucking and probing with finesse.

Too humiliated to admit he enjoyed the sting in his loins, Tanjirou wordlessly nodded and got another sharp slap as punishment. The globes of his ass were warm and red under Giyuu's hands. Though the man was interested to explore this newfound discovery, he was finished with teasing his adorable lover and pushed his cock between his creamy thighs, which were still wet from sweat and cum.

"Squeeze your thighs," he grunted out as he picked up the pace of his thrusts, making sure to slide their cocks against each other with each plunge. Giyuu continued to fuck between his legs without pause and pounded straight to his thighs in rapid-fire succession until Tanjirou felt himself harden from the friction.

Tanjirou clenched his thighs and whimpered as Giyuu nipped his neck, gripping his hips with brute strength. Together, they were sloppy and wet, horny and synchronized as they were staved from their climax. Tanjirou felt a building pressure within his core and noticed how their cocks twitched in tandem.

"Please, please, please," he said more desperately. "So close, so good," he choked out before his mouth was overtaken and trapped in a dance.

Giyuu lost all inhibitions and drowned in Tanjirou's cries. His arms locked around his thighs and added more friction, keeping his lover flushed against his chest because Tanjirou belonged to him and him only. Nobody will have the opportunity to see how much he begged for his cock, how he sang only for him. He monopolized his heart, and therefore, his everything.

Their mouths were locked, but they still cried out their names as they peaked and saw the sun, the sky, and the stars. The world ended as they painted each other with their seed and looked at each other with adoration in their eyes. All that remained was the heady smell of sex and cum and their panting selves, limbs wrapped around each other as if they were the last beings on earth.

"We're gross," Tanjirou quietly laughed as Giyuu stole his lips once more. Training was going to be a pain in the ass, but at the very least they were sated and glowing.

"Let's stay like this just a bit," he said and suckled a mark he left on his shoulder, reverting back to his more subdued self.

Easily convinced, especially when facing something as cute as Giyuu's post-coital bliss, Tanjirou weakened his resolved and cuddled in the man's arms. He may be late to training just this once, but it was a small sacrifice.

However, he later learned that it might a heftier sacrifice than expected, especially when he was given knowing looks from Zenitsu's traumatized eyes. The daggers he pierced him became even sharper the next night when Giyuu rewarded him for being a good boy.


End file.
